Lightweight, portable, vibrating, concrete screeds of the type to which the present invention is related are described in applicant's prior U.S. Pat. Nos. 4,030,873; 4,213,749 and 4,253,778. The general state of the art with respect to such type vibrating concrete screeds is believed to be fully set forth in these references and therefore will not be restated.
As another aspect of the prior art, it has been previously known to provide a screeding apparatus which is also adapted to form a curb on one side of the slab being screeded. For example, U.S. Pat. Nos. 3,224,348 and 3,377,933 teach apparatus which is designed to both screed a concrete slab and simultaneously form a curb on one side of the slab being screeded. However, it will be noted that this type of prior art represents an extremely heavy and relatively complex and therefore relatively expensive type of apparatus. As a general observation, so far as applicant is informed, it can be said that there has not been available a lightweight, portable, vibrating-type concrete screed having the ability to screed an entire roadway simultaneously with forming curbing on both sides of the roadway. Thus, it would be desirable to have curb forming apparatus which could be associated with the type of lightweight, portable, vibrating screed taught by applicant's prior patents and which could be utilized to form curbs on both sides of the roadway being screeded and with the ability to form crown and valley-type formations in the roadway contour. The provision of such an apparatus thus becomes the primary object of the present invention. Other objects will become apparent as the description proceeds.